1. Field of the Invention
The present invention relates to collection systems for self sustaining energy sources. More particularly, the invention comprises a solar thermal collector which heats both gas and liquid in separate circuits and also provides wind and photovoltaic electrical generation. The collector is associated with a thermal reservoir for storing thermal energy. The generator can power a fan and a pump for thermal collection, and optionally augment heat stored in the reservoir with resistive elements powered by the generator. A number of additional self sustaining energy generation systems could easily be adapted to complement solar and wind sources, as well.
2. Description of the Prior Art
It is desirable to exploit solar energy for heating, ventilating, and air conditioning for economic, practical, and environmental reasons. Systems employing solar power incur neither economic nor environmental fuel costs. In some applications, other sources of power are not readily available. In such applications, a self contained heating, ventilating, and air conditioning system would be both feasible and practical for providing heating, ventilating, and air conditioning services to a building. For example, a house or other building located remotely from readily available electric utility power could be heated, cooled and supplied with electricity by a self contained system.
Solar energy may be collected by photovoltaic cells which convert solar energy directly into electrical power. Alternatively, energy may be collected by photothermal collectors which convert solar energy directly into heat. Electricity is quite versatile in that it can be readily converted into either heat or made to generate mechanical energy for driving diverse machines. However, at the current state of the art, efficiency of thermal collectors greatly exceeds that of photovoltaic cells. Therefore, ideally a self contained heating and cooling system is reliant upon photothermal conversion for maximal energy capture and also upon photovoltaic conversion to power ancillary functions necessary to operate fluid heat transfer systems.
The prior art presents many attempts made over a long period of time to harness the sun. U.S. Pat. No. 4,098,263, issued to Joseph A. Lanciault on Jul. 4, 1978; U.S. Pat. No. 4,289,117, issued to Harry L. Butcher on Sep. 15, 1981; U.S. Pat. No. 4,333,448, issued to Steven A. Johnson on Jun. 8, 1982; and U.S. Pat. No. 4,526,162, issued to Nobushige Arai on Jul. 2, 1985, describe solar heat collectors, each comprising an enclosure having a cover closing a heating chamber and a fluid conduit disposed within the chamber for recovering entrapped heat. The devices of Lanciault, Johnson and Arai lack the light intercepting structure found in the novel photothermal collector, do not heat both liquid and gas separately and simultaneously, as in the present invention, and lack the supplementary wind and photovoltaic generating capability of the present invention.
U.S. Pat. No. 5,275,150, issued to Herman Lai on Jan. 4, 1994, presents a photothermal solar collector which provides a reflective bottom configured to reflect light against tubes containing a liquid being heated. These surfaces and tubes are parallel to the top transparent panel of the collector, rather than being perpendicular thereto, in the manner of the present invention. Lai further does not heat both gas and liquid, as does the present invention. Additionally, the solar collector of Lai lacks supplementary wind and photovoltaic generating capabilities, as seen in the present invention.
U.S. Pat. No. 4,551,631, issued to Gaetano T. Trigilion on Nov. 5, 1985; U.S. Pat. No. 5,075,564, issued to John J. Hickey on Dec. 24, 1991; and U.S. Pat. No. 5,394,016, also issued to Hickey on Feb. 28, 1995, describe combined wind and photovoltaic generators. These generators, however, lack photothermal collections capabilities found in the present invention.
U.S. Pat. No. 4,421,943, issued to Eric M. Withjack on Dec. 20, 1983, describes a photovoltaic element mounted on a portable base. Withjack lacks photothermal collection capabilities, wind generating capabilities and thermal storage capabilities, as found in the present invention.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.
The present invention provides a highly efficient photothermal solar collector which converts light rays to heat by intercepting these rays and converting them to heat prior to escape of the energy by reflection. The collector includes separate fluid paths for heating both a liquid medium, such as water or glycol alcohol, and a gaseous medium, such as air. The novel collector has a heating chamber having insulated walls and floor, and an insulated, light transmissive cover exposed to sunlight. The chamber contains hollow, open topped, metallic cylinders disposed between the floor of the chamber and proximate the cover. These cylinders are of a dark color for intercepting light rays and absorbing the heat contained therein prior to loss by reflection. A liquid conduit is likewise disposed in the heating chamber so as to also absorb heat entrapped within the chamber.
The solar collector also has a wind turbine and photovoltaic panels to provide additional energy in the form of electricity. The electrical energy may be employed to operate controls and fluid motive apparatus such as a pump or fan. If not consumed in moving heated fluids or for the operations of controls, generated electrical energy may be contributed to stored heat energy through resistive elements, or may be stored in batteries. Electrical energy, in excess of the needs of the system, may be directed from the system to commercial powers mains. A backup carbon fueled electricity generator may also be automatically actuated to power needed operations energy and battery charging capability whenever utility supplied electricity is interrupted, not present, or when power generated by the photovoltaic cells and/or wind powered generator is insufficient to maintain system operation.
To this end, the collector is connected to a remote thermal reservoir providing liquid storage capability. Heat can thus be stored for subsequent retrieval when the supply thereof exceeds demand. Heated air from the collector can be directed to the thermal reservoir to retain heat not captured by the liquid media. A suitable heat exchange system supplies heat from the reservoir to building space in the winter.
In the cooling season, the solar collector contributes to cooling by supplying heat to operate a heat-based cooling system, such as a system including a liquid absorption chiller. Therefore, a relatively uncomplicated, inexpensive device of significant efficiency contributes to both heating and cooling inhabited space.
In addition to solar and wind energy, the system can be readily adapted to capture energy from a variety of additional self sustaining sources.
Accordingly, it is a principal object of the invention provide a high efficiency photothermal solar collector.
It is another object of the invention to proved within the heating chamber apparatus disposed to intercept light and convert the same to heat prior to loss of energy by reflection from within the chamber.
It is a further object of the invention to enable both heating and cooling from a single solar energy source.
Still another object of the invention is to provide both heat and electrical power so that the heating and cooling system can deliver and remove heat from a building without relying on external power.
An additional object of the invention is to heat both a liquid medium and a gaseous medium simultaneously.
It is again an object of the invention to provide electrical energy in both the presence and absence of daylight.
Yet another object of the invention is to store thermal energy when the supply exceeds the demand.
Still another object of the invention is to be automatically controlled by a programmer or computer responsive to remote override adjustments.
It is an object of the invention to provide improved elements and arrangements thereof in an apparatus for the purposes described which is inexpensive, dependable and fully effective in accomplishing its intended purposes.
These and other objects of the present invention will become readily apparent upon further review of the following specification and drawings.